Paccar mx13 epa13 coolant in fuel!!!

[Nerv]

Hello all,

Just recently purchased two 2016 t660’s with Paccar mx-13 epa13 engines. First one changed the fuel doser and def doser no codes runs great and regen is working now. Second truck was at the shop, i get a message saying there is coolant in the fuel(never noticed this) showing up in the fuel water separator, these trucks are new to me. The fuel in the tanks was very cloudly as well could not see to the bottom. Just drained all the fuel out of the tanks and noticed a small amount of coolant at the bottom. Just put new fuel in, drained the fuel water separator and filled with fresh fuel until i can get new filters. What’s my issues here? Injector cups? Head? Or something else, no other symptoms really, theres no fuel in the coolant reservoir, no low power or misfiring. I know the head is {suspected to be made from compressed graphite iron (CGI) material} and the cups are part of the head, however a company just started making sleeves and the tooling for changing them(which is good). Either way, wanted to throw it out there to see what you guys think?

[Rawze]

most common cause is injector cups in the head leaking coolant into the fuel return lines. That or bad o-rings on the injectors.

[tree98]

Oops, I thought CGI was an aftermarket company lol

[Pd6cas2]

My Friend had the exact same issue. Artic Fox heater were leaking inside Fuel tank! 2 yrs ago when this happened’ they were back ordered 6 months, he just eliminated the heaters.

[Nerv]

(11-12-2023 )Pd6cas2 Wrote:  My Friend had the exact same issue. Artic Fox heater were leaking inside Fuel tank! 2 yrs ago when this happened’ they were back ordered 6 months, he just eliminated the heaters.

Yeah i was hoping that was the issue, I dont have heaters and Im not sure if the water separator has heating either. I ordered a set of new sleeves (non-OEM), going to see if the mechanic will buy the tooling for the job, if not ill just order it and do it myself. Seems like a pretty straightforward job. Can this issue arise from the head being cracked? Or would I have other symptoms from a cracked head?

[Pd6cas2]

I would call up the StealerShip Shop or stop by with Pizza and ask lots of questions. I’m in MN and my friend talks very highly of Rihm Kenworth here!

[Rawze]

(11-13-2023 )Nerv Wrote:  ... I ordered a set of new sleeves (non-OEM), ...

trying to save moneys on cummins engines is a BIG mistake long erm. You save nothing and the engine suffers before its all over with.

Its called jumping over a dollar to save a dime... and it is NOT A GOOD BUSINESS PRACTICE AT ALL WHEN REPLACING ENGINE COMPONENTS THAT COUNT!!!. It never ends well and causes a whole lot of grief in the long term.

[Colter]

Pull your injectors and pressure test your cooling system (to 5-psi only), that'll confirm a leak at an injector cup(s), I wouldn't replace cups unless you feel like doing this again within a year,

Personally I would replace the head, it takes no time to do but parts will be higher obviously, itll take the same amount of time to pull injectors as it would to pull the entire head, if its done by a competent tech it won't/can't take more then 16hrs, it'll cost 2-3 time more then cups but you'll be running without issues for a long while in comparison.

[Nerv]

{post remved by rawze... engine abuse}.